Tube Setting

[KarolinaMoon]

I am trying a bit of tube setting, and I am a bit confused about what sizes of burr's I require?! How do I work out what burr to use for each stone? Do i use the same size of burr for the same size of stone? i.e. a 5mm burr for 5mm stone and so on...

thanks for your help!

[EmmaC]

I've been using the same sized burr as the stone, but so far the limit to my tube setting experience is only 4mm CZ so I'm far from an expert on it!

[Gemsetterchris]

You generally end up using a burr the same diameter as the stone (or as near to as possible).
I usually start with abit smaller size & work up...
You can also use abit smaller burr if you don`t have the exact size.. Good to note if your "whatever size" burr is new, since quite often you`ll find they are abit worn & therefore don`t actually cut as big hole as you think..so you grab a bigger burr & end up with a too big hole.

[Patstone]

This question is nothing to do with the question I'm afraid. I have just been looking at your website and noticed an article on Moissanites. I bought one about 12 months or so ago and have it still sitting in my drawer waiting to be used. Question is, what is the difference between a moissanite and a C.Z apart from price that is. I know that C.Z's vary quite a lot and a good quality one really sparkles, but is about £5 ish for a 5mm one, and I paid about £35 ish for a 3mm moissaite.

[Gemsetterchris]

3mm moissanite are about £11 trade. I find they are abit better cut, at least the girdle are..cz`s are abit chunky..
Apart from that, it`s a different material & a fair bit harder & more scratch resistant.

[Dennis]

Could I also add that round burrs are cheaper and sharper when used on their sides, so you can use one of those first. Depending on how deep you go, they will do for several sizes. Then you can just finish with the more expensive setting burr.

Also using burrs in a pin vice, those with a wooden handle, and turning them by hand with a drop of oil, will preserve the burrs and create a more accurate seat. Dennis.

[EmmaC]

That's really interesting Dennis, as I've had dreadful problems getting a decent seat using them with a drill, so I'll try a pin vice next time :)

[Dennis]

If you don't already have them Emma, splash out on some six inch electronic callipers. There are bargains to be had, for instance from Maplin. You will be surprised at how much stones and burrs deviate from their stated diameter, when you are trying to match them up.

Those callipers have to be zeroed frequently though or they will lead you astray too. Dennis.

[EmmaC]

Thanks very much. I just checked and they have some in a Maplin that husband goes right past on the way to work! I've only got conventional calipers and they are not easy with such small stones which has probably made life more difficult for me. Had beginners luck on the first tube set I did, that has since evaporated :)